The invention generally relates to covers for medical instruments requiring optical transparency. Specifically, the invention entails a multipurpose, closed-end cover that is optically clear with surgical clarity throughout the closed end.
With the wide use of medical instruments that must remain sterile and require unobstructed optical clarity, the present cover provides a means for maintaining sterility and not inhibiting the scene. Use is compatible with different types of cameras, laser equipment, and other optically related instruments. This invention does not require the use of a lens or a special fenestration in the cover for viewing or functioning through.
A large variety of scopes have been developed to serve a physician's different needs during endoscopic surgeries. A surgeon may use several different scopes during one operation. Changing the sterile scope that had been attached to a non-sterile instrument such as a camera will compromise the sterility of the scope and therefore possibly the entire procedure. Others in the industry have provided covers for medical instruments used in endoscopic examinations that allows switching among similar instruments. A closed-end covering, which is embodied in U.S. Pat. No. 4,522,196, was developed that provides a permanent, semi-rigid, optically clear fenestration between the scope eyepiece and the camera lens. The use of a lens requires an extra seal around the lens and a means for implanting that lens into the plastic covering.
U.S. Pat. No. 4,522,196 is directed to a reusable, sterile covering for a surgical camera. The flexible covering is for use in combination with an endoscope and a camera that has a lens-to-endoscope coupling. The coupling temporarily couples the endoscope to the camera. The covering comprises a body portion for covering the camera and an end portion for enclosing the coupling and for defining a barrier by interposition between the camera and endoscope. The end portion is optically clear and made of material that is a rigid or semi-rigid relative to the flexible covering material. The clear end portion fits in the optical path between the endoscope and the camera. This covering is used for the same purpose as the present video camera sterilization embodiment, however, the '196 patent's covering in each embodiment is in combination with an optically clear aperture or member registered in the endoscope-to-camera optical path. In all embodiments, the '196 patent requires that the covering have a clear aperture portion or separate member attached to it or the covering is sealed around the clear portion. The '196 patent does not suggest or teach that the material used for the clear portion would comprise the entire sterile cover or that such a material exists that would be useful for replacement of the covering. It merely suggests that for the aperture, or separate member, that is to be registered in the optical path, a clear plastic film could be used at this portion. The video camera sterilization device of the present invention does not require a means for registering an optically clear aperture or member.
The semi-rigid fenestration of optically clear plastic must be correctly lined up with the eyepiece of the scope and the lens of the video camera for the image to be centered and completely and/or clearly shown on the monitor. The variety of camera sizes may make the fenestration size important for switching among instruments. The plastic film that is attached to the fenestration is somewhat stiff and not transparent. The alignment can be awkward, especially where sterile instruments are initially inserted into the cover during or for a sterile operative procedure.
The previous utilization of a lens or an optical portion construction can preclude clear viewing through the cover if the instrument moves inside the cover. Further, the seal around the lens increases the chance of leakage or other failure. No discovered prior art discloses a single-material, transparent polyurethane closed-end cover portion for a laser or a camera and camera lens coupled to an endoscope. The present application eliminates the separate and/or different material end portion of the cover and uses only a homogenous flexible optically clear, non-static polyurethane to cover the laser or camera lens and the rest of the camera body. The optical clarity can be distorted only by a very narrow seam if the camera or laser is not inserted in the center part of the cover. The cover must be misaligned at least 90.degree. for the seam to affect the image. The foregoing needs also exist in the medical field for other procedures.
Accordingly, it would be desirable to provide a totally clear closed-end cover, which is distortion free for surgical clarity, that can be used to maintain sterility of medical equipment. The present invention has an optically clear closed-end. Any portion of the polyurethane closed-end portion is sufficiently clear for optical use and there is no need to position a lens over the video camera. Moreover, it would be significant in the medical industry to provide a cover that is distortion free to allow accurate viewing of procedures being filmed.
In connection with the foregoing objectives, the chosen polyurethene material is optically clear so that one can see through any portion of the polyurethane closed-end portion with surgical acuity. There is no need to position a lens or specifically formed fenestration over a video camera or laser. Therefore, there is no need for a circular lens to fit over the lens of the camera itself, which abuts the eyepiece of the endoscope. Also, the optically clear, polyurethane, closed-end cover eliminates (1) the need to have a cover with a seal around an attached lens held in the cover, (2) means for implanting the lens in the plastic cover, and (3) the need for means to position a lens in the optical path between scope and camera.
It is a further goal of the invention to provide a cover where the closed-end portion applied to the medical instrument is compatible with lasers. Optical clarity improves the performance of a laser.
It is also a goal of the invention to provide a cover that conforms easily to different camera configurations. The present invention functions with direct in-line scope attachments and with scopes where the camera couplers are perpendicular to the camera. The camera couplers with the scope attached perpendicular to the camera can be used with the present device without concerns of aligning the cover or inserting a new cover because the present closed-end portion is optically clear.
Further, it is another intention of the invention to provide a cover that is supple, pleasant to touch, and durable. The specifications of the preferred components provides these attributes. Other aspects and benefits of the invention will be appreciated by those practicing medicine in each respective additional application of the cover.